Enlargement of fat cells and excessive accumulation of visceral fats triggers the onset of complex lesions of hypertension and hyperlipemia, diabetes mellitus, etc. These lesions are totally called metabolic syndrome, and recently have a large problem in human health, whereby its measures become an urgent business.
Visceral fat tissues secret endocrine components such as adiponectin, a plasminogen activator inhibitor, a tumor necrosis factor (TNF-α) and leptin and contribute to the maintenance of homeostasis in living bodies. However, when fat cells swell, the secretion of these components become abnormal and then excessive or insufficient. Recent studies show that breakdown of this balance is deeply involved in the onset or exacerbation of metabolic syndrome. Of these, the abnormal secretion of adiponectin is thought to have the largest effect (e.g., see non-patent document 1).
A is a molecule having 244 amino acids, is secreted from fat tissues, and exhibits not only the effect of insulin resistance improvement but also the effect of improving fat-burning in the liver and muscles. In addition, adiponectin is clarified to have the function of improving intake of glucose and fatty acid in blood into cells. Accumulation of fats in muscles and liver or the like worsens the intake of sugars leading to diabetes mellitus. However, usually, adiponectin seems to decompose fats and sugars that are temporarily excessive to maintain the nutrition balance in the body. When obesity progresses, the function of fat cells secreting adiponectin is weakened and the nutrition balance in the body is said to be broken. In this way, normality of adiponectin secretion is expected to have the effect of totally improving symptoms of metabolic syndrome such as hypertension, lipid dysbolism and diabetes mellitus.
Drugs or artificial compounds having the effect of increasing adiponectin are searched, but since there is the possibility of having side effects, attention has been paid to studies of food ingredients having functions like restraining the development of symptoms through eating habits as much as possible. As many extracts derived from plants are disclosed that include apple extracts (e.g., see patent document 1), spent hop extracts (e.g., see patent document 2), green tea catechin (e.g., see patent document 3), rice bran extracts (e.g., see patent document 4), turmeric extracts (e.g., see patent document 5) and the like. However, these have complicated extraction conditions and restraint of obtainment of extract raw materials, and exhibit decreases in taste when added to foods, their applicability as raw materials of formulations or eating and drinking products is questionable.
On the other hand, foods to which fermentation by lactic acid bacteria is applied are widely spread including cheeses and yoghurts and pickles and can be relatively inexpensively supplied and also have been produced in quantities in the world from old times due to their high acceptability. Additionally, Propionibacteraceae and yeast have been utilized for production of cheeses from old times and have contributed to fermentation of characteristic flavors (e.g., see non-patent document 2). These lactic acid bacteria, Propionibacteraceae, and yeast produce many decomposition products and metabolic products. Of these, although many health functional components have been found, still function-unknown components are thought to be present.
The present inventors have found that a peptide derived from milk protein separated from lactic acid bacteria aged cheese has the effect of promoting adiponectin production (e.g., see patent document 6). In addition, the present applicants have found that lactic acid bacteria cultures, particularly the cultures of Lactobacillus gasseri and Lactobacillus helveticus, using defatted milk culture media, have the effect of promoting increase and/or suppressing decrease of blood concentration of adiponectin (Japanese Patent Application No. 2006-244377).
Lactic acid bacteria are known to have prevention actions of pathogen infection (e.g., see patent document 7), prevention actions of inflammatory bowel disease and irritable bowel syndromes (e.g., see patent document 8), bone resorption suppression (e.g., see patent document 9), immunological enhancement actions (e.g., see patent document 10), prevention actions of diabetes mellitus complication (e.g., see patent document 11) and suppression actions of serum cholesterol increase (e.g., see patent document 12). However, culture supernatants which are liquid components prepared by removal of milk protein precipitates or bacterium components from cultures of microbes such as not only lactic acid bacteria but Propionibacteraceae and yeast are not known at all to have the effect of increasing adiponectin alone.
Milk protein precipitates and bacterium components coagulated by fermentation have a large effect on tastes of milk products, and sometimes deteriorate the qualities, lowering the product values. Technologies for removing precipitates from milk fermentation materials have also been developed (e.g., see patent document 13), and culture supernatants of milk fermentation materials that impart good tastes and high acceptability to foods have high industrial applicability as food raw materials.
[Patent Citation 1]
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